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Abstract Carbon fiber is the most common reinforcing phase in composite materials. However, it is difficult to obtain the performance parameters of the monofilament. In this study, the relationship between the property variables of the carbon fiber monofilament and the macroscopic parameters of the composites is established using a regression tree, a type of decision tree model, in machine learning. First, in order to obtain the data for machine learning, representative volume element (RVE) models of single-layer and multi-layer carbon fiber reinforced plastic (CFRP) are established by a cross-scale finite element method (FEM), and periodic boundary conditions are loaded. Then, a correlation model between the carbon fiber properties and CFRP and matrix properties is established. The non-GUI mode is called by Software Isight to generate the sample data. Second, in order to avoid overfitting, the L1 norm method is used for feature selection before model training. Finally, the four elastic properties of the carbon fiber are analyzed by a regression tree model. After a series of parameter adjustments and model selection, the model with a better generalization performance was obtained. The validity of the models was verified by the validating sample set. [ABSTRACT FROM AUTHOR]

A profile likelihood ratio test is proposed for inferences on the index coefficients in generalised single-index models. Key features include its simplicity in implementation, invariance against parametrization, and exhibiting substantially less bias than standard Wald-tests in finite-sample settings. Moreover, the R routine to carry out the profile likelihood ratio test is demonstrated to be over two orders of magnitude faster than the recently proposed generalised likelihood ratio test based on kernel regression. The advantages of the method are demonstrated on various simulations and a data analysis example. [ABSTRACT FROM AUTHOR]

[Display omitted] • 1 possesses remarkable thermal and acid / base stability. • 1 shows efficient luminescence quenching ability towards TNP with a high K sv value selectively and sensitively in water. • 1 exhibits the great anti-interference ability and repeatability. Nitroaromatic compounds (NACs) can lead to various environmental pollution healh problems. In order to effectively recognize and sense NACs, a novel coordination polymers (CPs) with fluorescent characteristic [Zn 3 (btc) 2 (tpt)(H 2 O) 2 ]·4H 2 O (1) (tpt = tris(4-pyridyl)triazine, H 3 btc = 1,3,5-benzenetricarboxylic acid) has been triumphantly prepared as an fluorescence probe by solvothermal method. 1 possesses remarkable PH stability ranging from 2.0 to 12.0 and is also stable in different pure organic solvents. It should be noted that 1 manifests a fluorescence quenching response against the detection of selectivity and sensitivity towards 2,4,6-trinitrophenol (TNP) in aqueous solution. It also makes analysis on the limit of detection towards TNP, which is as low as 0.94 µM compared with most reported CPs sensors for TNP. Therefore, 1 can become a satisfactory sensor for TNP detection with remarkable selectivity, strong anti-interference and favorable recyclability. In addition, the quenching mechanisms were also discussed. It was supposed that the mechanisms of photoinduced electron transfer (PET) as well as resonance energy transfer (RET) might be the main influencing factors. [ABSTRACT FROM AUTHOR]

A new luminescence Cd(II)-MOF (1) ([Cd 3 (BTC) 2 (TPT)(H 2 O) 2 ]·4H 2 O, TPT = tris(4-pyridyl)triazine, H 3 BTC = 1,3,5-benzenetricarboxylic acid) was successfully synthesized under solvothermal conditions. 1 contains 3D framework which consist of Cd atoms and btc3− anions with the large channels along c axis. Then, tpt ligands locate in the channels by utilizing three N atoms to bridge two Cd1 atoms and one Cd2 atom. 1 not only possesses remarkable thermal stability, but also can steadily exist in different organic solvents and various acid/base solutions (pH = 3–12). Moreover, 1 can detect 2,4,6-trinitrophenol (TNP) and chromate (CrO 4 2−/Cr 2 O 7 2−) anions with high selectivity and sensitivity in water via the luminescent quenching. The detection limits of 1 for TNP and CrO 4 2−/Cr 2 O 7 2− are 6.23 μM and 2.13 μM/2.87 μM. The mechanism of TNP luminescence quenching may be attributed to photoinduced electron transfer and resonance energy transfer, and CrO 4 2−/Cr 2 O 7 2− quenching involves resonance energy transfer and competitive absorption of light. Additionally, 1 has the great anti-interference ability and repeatability for detecting TNP and CrO 4 2−/Cr 2 O 7 2−, which can display the feasibility of this material as a stable luminescent probe in aqueous system. Unlabelled Image • A new Cd(II)-MOF (1) was synthesized by solvothermal method based on TPT and H 3 BTC. • 1 possesses remarkable thermal and acid/base stability. • 1 can detect TNP and CrO 4 2−/Cr 2 O 7 2− with high selectivity and sensitivity in water. • 1 exhibits the great anti-interference ability and repeatability. [ABSTRACT FROM AUTHOR]

To enhance the antibacterial activity of natural rubber latex foam (NRLF), chitin was added during the foaming process in amounts of 1–5 phr (per hundred rubber) to prepare an environmentally friendly antibacterial NRLF composite. In this research, NRLF was synthesized by the Dunlop method. The swelling, density, hardness, tensile strength, elongation at break, compressive strength and antibacterial activity of the NRLFs were characterized. FTIR and microscopy were used to evaluate the chemical composition and microstructure of the NRLFs. The mechanical properties and antibacterial activity of the NRLF composites were tested and compared with those of pure NRLF. The antibacterial activity was observed by the inhibition zone against E. coli. NRLF composite samples were embedded in a medium before solidification. The experimental results of the inhibition zone indicated that with increasing chitin content, the antibacterial activity of the NRLF composites increased. When the chitin content reached 5 phr, the NRLF composite formed a large and clear inhibition zone in the culture dish. Moreover, the NRLF–5 phr chitin composite improved the antibacterial activity to 281.3% of that of pure NRLF against E. coli. [ABSTRACT FROM AUTHOR]

• A stable multi-functional luminescent Cu-MOF with a four-connected uninodal net has been successfully synthesized under hydrothermal conditions based on electron-rich ligands (tpt and H 2 tda). • 1 not only has excellent luminescent property, but also can steadily exist in different organic solvents and acid-based solution. • 1 exhibits excellent sensitivity and selectivity for detecting CrO 4 2− and PA in aqueous solution based on luminescence quenching response ability. • The regeneration and reusability of 1 for detection PA and CrO 4 2− in aqueous solution increase its application potential. A novel three-dimension (3D) Cu (II)-based metal-organic framework [Cu 2 (tpt) 2 (tda) 2 ]⋅H 2 O (1) (tpt = 2,4,6-Tri(pyridin-4-yl)-1,3,5-triazine, H 2 tda = 2,5-thiophene dicarboxylic acid) with a four-connected uninodal net has been successfully synthesized under solvothermal conditions. Compound 1 , as a dual function sensor for selective and sensitive detection of picric acid (PA) and chromate ions (CrO 4 2−) in solution, not only has high quenching constant and low limit of detection, but also can resist interference of analogues. Furthermore, 1 behaves excellent stability which can steadily exist in different organic solution and acid-based solution. In addition, the cycling experiments of PA- 1 and CrO 4 2- 1 indicate that 1 has satisfying reusability and promising application in the field of analytical chemistry detection. Meanwhile, the fluorescence quenching mechanism of 1 also be further discussed. Noticeably, the C-V experiment was introduced to further prove fluorescence quenching mechanism, to the best of our knowledge which is the first reported. [ABSTRACT FROM AUTHOR]

To design an effective fluorescence probe for sensing nitroaromatic compounds (NACs) and metal ions, a novel two-dimensional (2D) coordination polymer, {Zn2(NO3)2(4,4′-bpy)2(TBA)} (1) {H2TBA = 4-(1H-tetrazol-5-yl)-benzoic acid, 4,4′-bpy = 4,4′-bipyridine} was synthesized via a hydrothermal method. As expected, 1 presented varying degrees of fluorescence intensity changes for detecting and recognizing trace NACs with high selectivity and sensitivity in water solution. Moreover, 1 not only exhibited a highly selective fluorescence quenching effect on Fe3+ ions in aqueous solution, but could also resist the interference of various other metal ions. In addition, it has been found that the fluorescence quenching mechanisms among NACs and Fe3+ ions are mainly related to the interactions between the host group and guest molecules by energy and electron transfer. [ABSTRACT FROM AUTHOR]

A supramolecular compound, (HL)(4,4′-bpy) (1) (HL = 1,2-bis(3,5-dicarboxyphenyl)diazene oxide, 4,4′-bpy = 4,4′-bipyridine) with 2D + 2D → 2D 3-fold parallel interpenetrated layer feature, has been prepared which was investigated as selective sensing material for detection of nitroaromatic compounds (NACs) and metal ions, and exhibits significant fluorescence quenching toward NACs and high selectivity for detection of Fe ion. The result indicates that 1 is a promising multi-functional fluorescence probe for detecting and recognizing NACs and metal ions with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

Summary. This study aimed to explore significant differences in chemical composition among maca (Lepidium meyenii Walp.) types with different colors in Yunnan province, China. 1H-NMR spectroscopy, in combination with principal component analysis and partial least squares discriminant analysis, was used to investigate the compounds responsible for compositional differences. Different maca color types in Yunnan were clearly distinguished by 11 differential metabolites. Furthermore, network pharmacology results showed that 30 active components were related to Alzheimer's disease. Nine intersecting compounds among the 11 differential metabolites and 30 active components, namely, lysine, isoleucine, phenylalanine, β-hydroxybutyrate, tryptophan, pyroglutamate, proline, glutamine, and fructose, were used as bioactive markers to identify different maca color types. The results showed the bioactive markers among different maca color types holistically, providing a scientific basis for assessing the quality of commercial products derived from different maca color types. [ABSTRACT FROM AUTHOR]

Testicular dysfunction is distinguished by a deficiency in testosterone levels, which can be attributed to the occurrence of oxidative stress injury in Leydig cells. The empirical prescription known as Bushen Zhuanggu Tang, developed by a highly experienced traditional Chinese medicine practitioner with six decades of clinical expertize, aligns with the traditional Chinese medicine principle of "kidney governing bone". Researchers have demonstrated that the administration of BSZGT can effectively enhance testosterone production. The objective of this study is to investigate the potential anti-testicular dysfunction effects of BSZGT and elucidate its underlying mechanism in an in vitro setting. Specifically, the impact of oxidative stress induced by H 2 O 2 on the activity and testosterone levels of Leydig cells (TM3) was examined. Furthermore, the utilization of UPLC-QE-Qrbitrap-MS enabled the identification of the involvement of BSZGT in various metabolic pathways, including arginine biosynthesis, amino acyl-tRNA biosynthesis, Alanine, aspartate and glutamine metabolism, and Citrate Cycle, through the modulation of 25 distinct metabolites. Additionally, a network pharmacological analysis was conducted to investigate the pivotal protein targets associated with the therapeutic effects of BSZGT. The findings demonstrate the identification of six key proteins (CYP19A1, CYP1B1, ALOX5, ARG1, XDH, and MPO) that play a significant role in augmenting testicular function through their involvement in the ovarian steroid production pathway. In summary, our study presents a comprehensive research methodology that combines cell metabonomics and network pharmacology to enhance the discovery of new therapeutic agents for TD. [Display omitted] • The mechanism of Bushen ZhuangGu Tang in treating testosterone deficiency was studied. • Bushen ZhuangGu Tang's differential metabolites were identified combined with metabonomics and network pharmacology. • According to GO and KEGG pathways, Bushen ZhuangGu Tang may play a role in arginine biosynthesis. [ABSTRACT FROM AUTHOR]

Designed, synthesized, structure and fluorescent probe studies Ni-MOF based on tpt and m -H 2 bdc. • A stable Ni(II)-MOF has been hydrothermally synthesized based on tpt and m -H 2 bdc. • 1 has excellent thermal and chemical stability. • 1 exhibits excellent sensitivity and selectivity for detecting PA and CrO 4 2−. • 1 shows great anti-interferent ability and reusability for detecting PA and CrO 4 2−. A new luminescent compound Ni 4 (tpt) 4 (m -bdc) 4 ·H 2 O (1) (tpt = tris(4-pyridyl)triazine, m -H 2 bdc = m -benzenedicarboxylic acid) was successfully synthesized by hydrothermal method, and characterized using single-crystal X-ray diffraction, PXRD, TG analysis and IR. 1 possesses a four-connected three-dimensional (3D) topological network with the Schläfli symbols of {65⋅8}. 1 not only has excellent thermal and chemical stability, but also is a dual-functional luminescent sensor with high selectivity and sensitivity for detection of picric acid (PA) and chromate (CrO 4 2−) anions in water via the luminescent quenching. And the sensing mechanism for the quenching process was discussed in detail. Moreover, 1 can be regenerated by a fast and simple method in detecting PA and CrO 4 2−, showing excellent recyclability after the sensing experiment. [ABSTRACT FROM AUTHOR]

• A novel luminescent Zn-MOF 1 has been synthesized and structurally characterized. • Complex 1 is a 3D MOF constructed from the rare ligand p -phenylenediamine. • Complex 1 can be regarded as a potential chemical sensor for nitroaromatics (NACs) and Fe3+. • Mechanism of luminescence sensing for NACs was investigated. In this work, a novel three-dimensional (3D) complex [Zn 2 (bta)(ppda)] n (1) (H 4 bta = 1,2,4,5-benzenetetracarboxylic acid, ppda = p -phenylenediamine) has been synthesized under hydrothermal condition. Complex 1 exhibits high sensitivities towards the nitroaromatics (NACs) and Fe3+ ions in dimethylsulfoxide (DMSO) solution via fluorescence quenching. Specially, 1 as a fluorescence probe for sensing the Fe3+ ions has a large quenching coefficient K sv of 8.823 × 106 M−1 and a low limit of detection (LOD) of 4.664 × 10−4 μM. [ABSTRACT FROM AUTHOR]

Background: The processing of Chinese materia medica is an important part for the preparation of traditional Chinese medicine (TCM) which has been believed that can change the chemical composition and physiological function. Velvet antler is a kind of precious TCM and widely used after hot processing as folk medicines in China. However, no strategy has been presented to reveal the processing principle of velvet antler. Objective: The aim of this study is to develop a method for exploring the mechanism of hot processing on velvet antler. Materials and Methods: In this study, the chemical compositions of fresh velvet antler (FVA) and hot processed velvet antler (HPVA) were compared based on the 1H nuclear magnetic resonance (1H NMR) and multivariate statistical analysis methods to explore the mechanism of hot processing on velvet antler. Results: It showed that hot processing increased phosphorylcholine, taurine, alanine, uridine, phenylalanine, uracil, tyrosine, accompanied by decreased bile acid, choline, lipid 2 and succinic acid in comparison to the FVA, which changed significantly in 52 common metabolites of FVA and HPVA. In addition, a clear separation between FVA and HPVA was obtained by using principal component analysis and 11 "chemical markers" were found by using orthogonal partial least squares discriminant analysis (OPLS-DA) approaches. Particular attention was given to the "chemical markers" with potentially beneficial bioactivities. Conclusion: The study demonstrated that 1H NMR-based chemometric approach could be a promising tool for investigation of the hot processing of velvet antler in a holistic way of TCM. [ABSTRACT FROM AUTHOR]

Abstract A novel luminescent metal-organic framework (MOF) {[Co 3 (phen) 2 (HL) 2 ]·(H 2 O) 2 } n (1) (H 4 L = 3,3′,5,5′-azoxybenzenetetracarboxylic acid, phen = Phenanthroline) was successfully prepared under solvothermal conditions. Its structure has been identified by single-crystal X-ray diffraction, infrared spectroscopy, elemental analysis, powder X-ray diffraction and thermogravimetric analysis. Additionally, the importance of the weak interactions to stabilize the structure of 1 has been discussed by Hirshfeld surfaces and the corresponding 2D fingerprint plots (FPs). Remarkably, 1 has high thermal stability up to 360 °C and excellent chemical stability in water with wide pH range of 2–11. Luminescence studies show 1 can recognize Fe3+ and Al3+ with high selectivity from mixed metal ions in aqueous solutions through the luminescence quenching and enhancement phenomenon, respectively. Furthermore, 1 can also detect PA with good selectivity and sensitivity among large common nitro-aromatic compounds (NACs). Graphical abstract A novel Co(II) metal-organic framework as a multi-functional luminescent sensor exhibits a highly selective luminescence quenching to Fe3+ and picric acid, and highly sensitive luminescence enhancement for Al3+in aqueous solution. fx1 Highlights • A novel luminescent MOF 1 has been synthesized and structurally characterized. • MOF 1 can detect Fe3 + and Al3 + ions through different luminescence responses. • MOF 1 can also be a potential sensitivity chemosensor for PA. • Mechanism of luminescence sensing for Fe3 + , Al3 + and PA was investigated. [ABSTRACT FROM AUTHOR]

Ternary reduced graphene oxide nanosheets (rGSs)/Fe 2 O 3 /polypyrrole (PPy) hydrogels with Fe 2 O 3 nanoparticles (NPs) embedded between rGSs and PPy layer were prepared in one-pot. The ternary hydrogels exhibited an interconnected and porous three-dimensional network with co -existence of macropores and mesopores. Fe 2 O 3 NPs uniformly dispersed on rGS surface with the diameter of 8.8 nm. Control experiments were carried out to investigate the roles of components in formation of ternary hydrogels. During heterogeneous Fenton degradation of methylene blue (MB) dyes, the ternary hydrogels exhibited much better removal efficiency than the reference samples, not only because rGSs and PPy layer altered the adsorption, dispersity and diameter of Fe 2 O 3 NPs; but also owing to the structural merits of ternary hydrogels. The effects of operating conditions, such as initial MB concentrations, dosages of catalysts and H 2 O 2 , were carefully investigated. With the help of Fe 2 O 3 NPs, ternary rGSs/Fe 2 O 3 /PPy hydrogels could be easily separated via a magnet. In recycling experiments, they showed superior reusability. [ABSTRACT FROM AUTHOR]

Two new inorganic-organic hybrid materials [Cu(enMe) 2 ] 2 {(As 2 Mo 6 O 26 ) [Cu(enMe) 2 ]}·4H 2 O ( 1 ) and [As 2 Mo 6 (OH) 2 O 24 ][Cu(H 2 O) 2 (phen)] 2 ( 2 ) (enMe = 1,2’-propanediamine, phen = 1,10’-phenanthroline) based on [As 2 Mo 6 O 26 ] 6- building blocks, denoted as [As 2 Mo 6 ], have been obtained by hydrothermal methods. 1 shows a 1-D straight chain structure constructed form [As 2 Mo 6 ] building blocks and [Cu(enMe) 2 ] complexes, and then extended to 3-D supramolecular network by lattice water via hydrogen bonds interactions. 2 exhibits a new 1-D covalent ribbon with large rectangular grids formed from [As 2 Mo 6 ] building blocks connected by [Cu(H 2 O) 2 (phen)] complexes, then extended into 3-D supramolecular network via hydrogen bonds and π···π interactions. In additional, the photocatalytic activity for methylene blue degradation under visible-light irradiation of 2 was investigated. [ABSTRACT FROM AUTHOR]

Metal nanoparticles (NPs) displayed overwhelming superiority in catalysis towards the corresponding bulk-phase materials; nevertheless, how to further improve catalytic activity was still an ongoing subject. Herein, we have combined one-step redox reaction and following freeze-dried technology to construct the quinary reduced graphene oxide nanosheets (rGS)/Fe 2 O 3 -PdPt/polypyrrole (PPy) hydrogels. Compared with traditional catalysts, their catalytic property was improved via two ways: construction of three-dimensional (3D) rGS hydrogels instead of two-dimensional rGS and synthesis of bimetallic alloys instead of monometallic NPs. The highly dispersed PdPt with diameter as small as 3.2 nm uniformly loaded on hydrogel surface. Due to special interconnected and porous structure, the reactants were easily adsorbed in hydrogels and contacted with PdPt alloys. To explain the contributions of bimetallic alloys and 3D rGS structure on enhanced catalytic activity, the catalytic property of quinary hydrogels was compared with reference samples. Besides superior activity, they also displayed good reusability, since hydrogels could be magnetically recycled owing to the existence of Fe 2 O 3 NPs. [ABSTRACT FROM AUTHOR]

Forkhead Box O1 (FoxO1) is a transcription factor with a unique fork head domain that indirectly participates in a variety of physiological processes and plays an important role in type 2 diabetes. Palmitate as the most abundant free fatty acid, accounting for 28–32% of total free fatty acids in human plasma. There is a direct relationship between palmitate and insulin resistance-induced type 2 diabetes. In addition, palmitate can activate the unfolded protein response signaling pathway induced by endoplasmic reticulum (ER) stress. This study aimed to investigate the response of FoxO1 to palmitate and the relationship with ER stress in C2C12 myotubes. Treatment of palmitate or tunicamycin promoted ER stress-related genes expression but suppressed FoxO1 expression, while 4-phenylbutyrate presented the opposite activity in palmitate-pretreated C2C12 myotubes, indicating that ER stress might be closely associated with FoxO1 expression. Moreover, palmitate-suppressed FoxO1 expression was reversed in C2C12 cells when the PERK and IRE-1 signaling pathway was inhibited by treatment with GSK2656157 or 4μ8C. However, no differences were observed when the ATF6 signaling pathway was suppressed by knockout of the ATF6 gene. These findings suggest that palmitate suppressed FoxO1 expression via the PERK and IRE1 signaling pathways. [Display omitted] • This study demonstrated that palmitate inhibited FoxO1 expression in C2C12 mouse myotube cells. • Palmitate activated ER stress in C2C12 mouse myotube cells, indicating that ER stress may mediate FoxO1 expression. • Inhibitors of PERK and IRE-1 signaling reversed palmitate-reduced FoxO1 expression. • These findings suggest that palmitate suppressed FoxO1 expression via the PERK and IRE1 signaling pathways. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel luminescent metal–organic complex (MOC) 1 has been synthesized, which has unique structure. • Complex 1 is the first three-dimensional (3D) coordination polymer constructed from ppda and Co2+ ions. • Comple x 1 can be regarded as a potential fluorescent probe for nitro-aromatic complexes (NACs) and Fe3+ ions. • Mechanism of luminescence sensing for NACs and Fe3+ ions were discussed. A luminescent Co (II)-based coordination polymer [Co 2 (bta)(ppda)(H 2 O) 2 ] n (1) (H 4 bta = 1,2,4,5-benzenetetracarboxylic acid and ppda = p -phenylenediamine) was synthesised by hydrothermal method and characterized by single-crystal X-ray diffraction, which is the first three-dimensional (3D) coordination polymer constructed from ppda and Co2+ ions. Furthermore, fluorescence studies indicated that 1 displays high sensitivity for both nitroaromatic complexes and Fe3+ ions via fluorescence quenching effect. [ABSTRACT FROM AUTHOR]